Sidewinder rattlesnakes, or crotalus cerastes, are native to the arid desert regions of the southwestern United States. They are particularly adapted to move over sandy terrain, camouflage themselves both for hunting and defense, and travel underground through burrows.
As their name implies, sidewinders move with a distinctive sideways motion. According to the San Diego Natural History Museum website, this movement puts pressure on the ground, holding sand in place so the snakes don't slip as they travel. In addition, sidewinders raise up most of their bodies to effect this movement, reducing their contact with hot sand and other surfaces that might burn their scales.
Sidewinders are usually tan, brown, cream, gray or pink, with darker patches on their backs. The color and gradations of their scales closely match the shade and texture of desert sand, which helps conceal them from both predators and prey.
One of the sidewinders' most distinctive features are their "horns," or upturned scales above each eye. These scales fold down to protect the sidewinders' eyes when they travel through narrow burrows in search of prey or to escape heat.
During spring, when temperatures are mild, sidewinders may be active during the day or night. When desert heat becomes extreme during the summer, sidewinders shift to hunting and feeding at night. They may also hibernate during the hottest part of the summer, as well as through the winter.
Juvenile sidewinders hunt primarily lizards, while adults prefer kangaroo rats and other desert rodents. The snakes are ambush hunters, often covering themselves with sand for camouflage and then waiting for prey near game trails and dens.